This invention relates to latching and locking mechanisms for doors of passenger vehicles.
Vehicle doors are commonly provided with interior and exterior door handles operable from the inside or the outside of the vehicle respectively to release latching means of the door for opening it. Provisions are also made for locking the door to resist unauthorised access by locking means acting to disable or block the latch mechanism to prevent the door being freed when closed. Even if the locking means is power operable, for example as part of a central door locking system, provisions will be made on at least some of the doors for manual locking and unlocking at least from the vehicle interior is. This commonly provided by a manual push-pull button or the like, typically a cill button, separate from the interior door handle which adds to the cost and complication of the door mechanism, and may also involve additional costs in terms of layout to suit the mechanism to particular styles of door, and in terms of making the mechanism tamper-resistant for effectively deterring attempted theft of the vehicle or its contents.
According to the invention there is provided a vehicle door mechanism including self-acting latching means operatively holding the door closed and including a latch release member selectively moveable from a neutral position to a release position freeing the door for opening. The mechanism further includes locking means acting to secure the latched door by preventing release actuation of the latching means and including a lock drive member selectively movable between locked and unlocked positions. The latch release member has a path of travel extending between the release position and a door secure position, said neutral position being in an intermediate part of the path. The release member and the lock drive member are coupled by motion transmitting means including a first formation on one of the members co-acting via a connecting means with a second formation on the other of the members to shift the lock drive member to the locked position on movement of the release member from its neutral position to its door secure position. Preferably the connecting means is one or both of a link or a resilient connection.
Preferably where a resilient connection is provided, the resilient connection acts in compression and is arranged to reach a state of maximum compression during at least part of the operation of the locking mechanism. The resilient means can be a spring.
Preferably the spring is a helically wound spring that becomes coil bound during at least part of the operation of locking the mechanism.
Preferably resilient means acts between the members to ensure the lock drive member returns to its unlocked position on return movement of the release member from the door secure position to or beyond the neutral position. The resilient means permits travel of the release member to its release position but urging or contributing to the urging of the member from that position to the neutral position.
Conveniently either or both of the latch release and lock drive members are bell crank or other levers which may be fulcrumed about separate parallel axes or, possibly, fulcrumed for movement about a common axis.
The latch release member will typically be connected by a linkage to an interior handle of the door so that the latter serves both to open the door and for its locking and unlocking.
Embodiments of the invention are now more particularly described by way of example and with reference to the accompanying drawings, wherein;